6 



foote: total emissivity and resistivity 



Table II shows the corrections which must be apphed to the 

 temperature observed with a radiation pyrometer, when sighted 

 upon pure platinum, in order to obtain the true temperature of 

 the radiating platinum. The temperature of the receiver is con- 

 sidered as 300° abs. 



TABLE I 

 Total Emissivity vs. Temperature 



TABLE II 

 Total Radiation Pyrometer Sighted on Platinum 

 (Receiver = 300° abs.) 



In a subsequent paper the emissivity of other metals will be 

 discussed. Approximate measurements have already indicated 

 that equation (7) is a general relation, and is by no means re- 

 stricted to the example cited in the present paper. 



SUMMARY 



A definite relation has been found to exist between the total 

 emissivity and the volume resistivity of a metal. This relation 



